Experiment to test TCP keepalive for pop3d proxies

[Wesley Craig]

On 01 Jun 2010, at 14:05, Gary Mills wrote:
>     # pstack 12708
>     12708:  pop3d -s
>      feb1a5c5 read     (0, 817faf0, b)
>      fec2dfaf sock_read () + 3f
>
> I don't know why the stack trace is so short with these.

Thinking about this a little more...

sock_read() is probably from openssl's BIO layer, and the stack trace  
is probably truncated because pstack can't follow the backtrace  
through the function pointer that SSL_read() is using to access  
sock_read().  This is an SSL connection, right?  Take a look at the  
SSL_read() man page, for an idea of what can go wrong.  Having  
written something very much like the prot suite for another project,  
I can say that SSL is really much happier with non-blocking IO, if  
you're hoping for control to return to the call at some point.

:wes